How does Ohio's medical marijuana policy compare to policies in other states?

FILE - In this Dec. 27, 2013 file photo, an employee trims away unneeded leaves from pot plants, harvesting the plant's buds to be packaged and sold at Medicine Man marijuana dispensary, in Denver. States that have legalized pot are taking a fresh look at making it easier for out-of-state investors to get in the weed business, saying the pot industryís ongoing difficulty banking means they need new options to finance expansion. (AP Photo/Brennan Linsley, file)

Brennan Linsley

Copyright 2016 Scripps Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

With Governor John Kasich’s Wednesday approval of a law legalizing medical marijuana in Ohio, exactly half the states in the union (plus Washington, D.C.) permit the use of cannabis in some form.

Because the federal government’s official policy on cannabis use still states that it is a crime to buy, sell or use marijuana under any circumstance, individual state government policies form a patchwork quilt of different restrictions and requirements without much overall guidance.

In Colorado, for instance, it is perfectly legal to use marijuana products recreationally. But in Wisconsin, the only legal cannabis product is cannabidiol, an oil extract used to treat children with severe epilepsy. In Washington, D.C., it is legal to buy, grow and use marijuana but not to sell it.

Starting in September, Ohioans will have access to medical marijuana — but what does “medical marijuana” even mean? Who can get it, and what conditions can it be used to treat? Those answers, too, are different from state to state.

This policy approves cannabis treatment for a broader range of conditions than many other states, but comes with a few caveats: the products in question must be oils, patches or edibles, marijuana will not be covered by insurance and local governments can still decide to ban or limit marijuana dispensaries.

By contrast, Illinois, which has one of the most expansive medical marijuana policies in the country, allows physicians to prescribe cannabis products for nearly 40 conditions, and these products can be smoked, eaten, vaporized or applied to the skin as a balm.

Where do other states fall? Here’s a visual guide (to expand this graphic, click here):